Update README to include links to all API functions.
Update README to include links to all API functions.

Some of these ones are hard to find at a quick glance. Putting them in the index makes them easier to spot and find.

carck/async,rborisov/async,renruixi/async,SaiNadh001/async,lonely8rain/async,caolan/async,FrankSunnyvale/async,hargasinski/async,evdevgit/async,caolan/async,ezubarev/async,megawac/async,SaiNadh001/async,sjclijie/async,evdevgit/async,mingqi/uclogs-async,andalm/async,modulexcite/async,hargasinski/async,mcanthony/async,imjerrybao/async,pandoraui/async,RickyDan/async,kolomiichenko/async,bjlxj2008/async,ibakaidov/async,chaddm/async,Segeon-Kim/async,steverobb/async,tjwudi/async,rlugojr/async,ibakaidov/async,ariesnah/async,justincy/async,lonely8rain/async,pandeysoni/async,scq000/async,llwanghong/async,ArcadiusK/async,andyburke/antisync,r14r/fork_javascript_async,Connectlegendary/async,bjlxj2008/async,Segeon-Kim/async,gypsydave5/async,andyburke/antisync,jamesjnadeau/async,pandeysoni/async,moander/async,haggholm/async,Kikobeats/async,haggholm/async,jaruba/async,pandoraui/async,markyen/async,chaddm/async,rborisov/async,DDunc/async,renruixi/async,Qix-/async,xiebaochun/async,beni55/async,steverobb/async,KnottedRain/async,jaruba/async,DanieleTassone/async,garysye/async,megawac/async,carck/async,beni55/async,zhhb/async,DaAwesomeP/async,youprofit/async,wrenth04/async,DaAwesomeP/async,ezubarev/async,ArcadiusK/async,Zhang/async,imjerrybao/async,navyxie/async,ecasilla/async,abhishekgahlot/async,Connectlegendary/async,DanieleTassone/async,ariesnah/async,youprofit/async,lanffy/async,garysye/async,XM-Right/async,suguru03/async,kolomiichenko/async,wrenth04/async,Qix-/async,Zhang/async,RickyDan/async,navyxie/async,wushuyi/async,tjwudi/async,virtdb/async,r14r-work/fork_javascript_async,arigo-software/async,r14r/fork_javascript_async,LeoYao/async,r14r-work/fork_javascript_async,mcanthony/async,DDunc/async,justincy/async,FrankSunnyvale/async,lanffy/async,mingqi/uclogs-async,ecasilla/async,scq000/async,llwanghong/async,zhakui/async,jamesjnadeau/async,xiebaochun/async,modulexcite/async,rlugojr/async,Segeon-Kim/async,Kikobeats/async,LeoYao/async,arigo-software/async,JulianVolodia/async,jnordberg/async,abhishekgahlot/async,JulianVolodia/async,zhakui/async,gypsydave5/async,jnordberg/async,sjclijie/async,KnottedRain/async,suguru03/async,wushuyi/async,zhhb/async,andalm/async,markyen/async,moander/async,XM-Right/async